(a) Field of the invention
The present invention relates to a video image processing apparatus and the method of the same for reducing plural compressed video images, and displaying the plural reduced images simultaneously in divided portion on a same screen.
(b) Description of the Prior Art
At the present, when editing video materials taken, for example, by a video camera or the like in a broadcasting station or post-production, digitized video image is once stored and saved in a hard disk (HDD) of video editor or video server, and the so-called nonlinear editing is widely employed, that is, while monitoring the contents of video materials in the HDD, cuts are exchanged, inserted or deleted, and editing or transmission is done. In such editing work, for example, the video material recorded in a video cassette is read at high speed by a VTR, and the transfer time to the HDD is shortened.
FIG. 3 is a diagram showing an example of such editing application of video material.
In FIG. 3, reference numeral 301 is a video camera, 302 is a video cassette in which a video material is recorded by the video camera 301, and 303 is an n-times speed video player, which is a VTR capable of reading the video cassette 302 at a speed of n times of the normal speed. Reference numeral 305 is a video image processing apparatus. Reference numeral 306 is a video monitor. Reference numeral 304 is a nonlinear video editor having an HDD.
The video material taken by the video camera 301 is recorded in the video cassette 302. This video camera is read by the n-times speed video player 303, and is transferred at high speed into the HDD in the nonlinear video editor 304.
For transfer to the HDD, in order to shorten the transfer time, the n-times speed video player 303 capable of reading the video cassette 302 at a speed of n times of the normal read/write speed is employed. In the n-times speed video player, video image signals of n frames are read in an ordinary period of one frame. Such n-times speed video player 303 is easily realized by mounting n times of head of the number of ordinary reading magnetic heads on the cylinder of the VTR, and running the tape at n times of normal speed.
The operator of editing work, in order to monitor the content of the video material recorded in the video cassette 302 in the process of transfer of video image signal of the video material into the HDD in the nonlinear video editor 304 from the n-times speed video player 303, manipulates to display the content of the video image signal in the process of transfer of video image signal from the n-times speed video player 303 into the nonlinear video editor 304, on the video monitor 306 through the video image signal processing apparatus 305.
In the case of n-times speed reading, n times of video image signals of the normal reading data are obtained from the VTR. That is, video image signals of n frames are read in an ordinary period of one frame. Therefore, in order to display all frames of the video image signals being read on the video monitor 306, it is necessary to reduce the video image, and display the plural reduced images simultaneously in divided portions on one screen.
As the video image processing apparatus for reducing plural video images and displaying the plural reduced images simultaneously in divided portions on one screen (corresponding to the video image processing apparatus 305 in FIG. 3), for example, U. S. Pat. No. 5,434,624, Jul. 18, 1995 ("Apparatus for producing a multi-scene video signal" Tsuneaki Ishimura) is disclosed.
According to this publication, delay circuits for delaying an input video image signal and the address corresponding to this video image signal are provided, and their outputs are selectively passed and written into the memory, so that the video image is reduced and displayed.
Such prior art, however, involved the following problems.
When the plural input video images arc compressed video image signals, for example, if compressed by using a DCT transform (Discrete Cosine Transform), the sample of the video image is the concept of the frequency, and when recorded in a VTR, VLC encoding or the like is employed, and therefore the concept of the address signal in the prior art is lost, and the method of the prior art cannot be employed.
If it is dared to apply the method of the prior art in the compressed video image, in the stage before input in the prior art, a circuit for expanding the compressed video image until becoming completely uncompressed is required, and the expander circuits are required as many as the number of input images, so that the circuit size becomes very large.